Boiler tube scraper



June s, 1945. t, J. LUOX l 2,377,598

BOILER TUBE SCRAPER Filed Aug. 26, 1941 Zhi/vena;

Patented June 5, 1945 UNITED STATES PATENT oFFlcE BOILER TUBE SCRAPER`John Zilliox,`rchard Park, N. Y., assigner to Raymond'G. Blendinger,Buffalo, N. Y.

, Application August 26, 1941, Serial No. 408,362 I This inventionrelates to certain new and useful improvements in tools for cleaning orscraping the tubes of boilers and the like.

It has for one of its objects to provide a tool of this character whichis so designed and constructed as to eifectually and economically removesoot and scale from the tubes and at the same time burnish the tubes toa smoothness that will prevent such soot and scale from re-forming soquickly.

Another object of the invention is to provide a scrapingtool for boilertubes and the like which may be operated by air, steam or water andwhose scraper blades are so mounted as to automatically adjustthemselves to the surface of the tube irrespective of its shape orcondition.

A still further object is to provide a boiler tube scraper which issimple and inexpensive in con-I structiony which is durable and reliablein operation, and which promotes and maintains maximum boilerefficiency.

Other features of the invention reside in the construction andarrangement of parts hereinafter described and particularly pointed outin the appended claim.

In the accompanying drawing:

Figure 1 is a fragmentary side view, partly in section, of a boiler tubeassembly showing my improved scraper in an operative position in one ofthe tubes. Figure 2 is an enlarged, central longitudinal section of thescraper. Figure 3 is a cross section thereof in operative positionWithin atube. Figure 4 is a fragmentary sectional view of the bladed endof the tool.

i By way of example, my improved scraper has been depicted in Figure 1in an operative position in one of the tubes II) of the boiler tubeassembly II, the numeral I2 indicating the body or casing of thescraper, I3 the scraping blades Whi-ch are adapted to rotatably bearagainst the soot or scale to remove such matter from the tube, and I4in- The body I2 is substantially cylindrical and in its duid-receivingchamber I5 is a stator I'I whose flanged front end I1 abuts at its innerend against a forwardly-facing shoulder I8 formed in the body and whoseperipheral face has a snug fit with the inner side of the body to forman air tight closure therefor. Bolts I9 serve to effectually secure thestator in place within the body, as shown in Figure 2, wherein it willbenoted that the front face of the stator terminates short of the frontend of thebody for a purpose which will hereinafter appear.

Carried by and journaled in suitable bearings in the stator IB is theblade-carrying rotor assembly preferably consisting of a rotatable shaftor member disposed axially of the stator to rotate freely relativelythereto. Secured to the front end of this shaft, which may be in theform of a bolt to permit ready assemblage of the parts, is an impellerwheel 2I having obliquely-disposed vanes 22 projecting from itsperiphery, said wheel adjoining the front face of the stator and operat`ing within the front end of the body I2. A plurality of ports 23 arearranged in the statorflange 'I for directing the fluid mediumintroduced into the body I2 tangentially against the rotor vanes 2,2 torotate the impeller at a high speed.

Detachably mounted on the rotor assembly forwardly of the impeller wheel2| are a plurality of scraper blades I3 which are free to respond to thecentrifugal force developed by the high speed rotor and to beself-adjustable and directed rm- 1y into engagement with the boiler tubeWalls to effectually scrapeand clean the soot and scale therefrom. Bypreference, two of such scraper blades a're provided and each consistsof a body 24 terminating at one end in a laterally or obtusely bentscraper tip or face 25 and at its other end in a hinge-loop 26 pivotallymounted on a spindle or bolt 21 projecting forwardly from the impellerWheel 2l at one side of its axis and disposed parallel therewith. Asshown in Figures 2 and 3, a tie bar 28 connects both hinge-bolts 2l attheir free ends and nuts 29 serve to removably retain the scraper bladesthereon. Projecting forwardly from the face of the impeller wheeladjacent each hinge-bolt is a stop pin 30 which is disposed in theoutward swinging path of the companion scraper blade to limit itsmovement in that direction and wherein its scraper tip 25 is disposedsubstantially radially of the tube, as shown in Figure 3. In thisconnection, it should be noted that the scraper blades are free to swinginwardly and are thereby self-adjustable to conform to the diameter ofthe tube bore as determined by its shape or by the degree of scalingthereon.

In operation, the tool is placed in the tube to be cleaned in the mannershown in Figure 1 and I the iiuid medium, whether air, steam or water isintroducedinto the pipe I4 to impart rotation to the rotor bladeassembly. The scraper blades I3 are projected by centrifugal forceagainst the tube wall and in so doing cling thereto and effectuallyscrape the soot and scale therefrom. As the soot and scale is removed,the scraper blades automatically adjust themselves and are maintained inrm scraping contact With the tube at all times, and, When the soot andscale is removed, the tube is burnished smooth to thereby prevent sootand scale re-forrning so readily. The exhaust :from impeller wheel 2lserves also to drive the cleanings from the tube and prevents clogging.In Figure' 3 the scraper blades are shown by full lines in burnishingcontact with the tube, While the dotted lines show the blades I claim asmy invention:l

A boiler tube scraper, comprising a cylindrical body open at its frontend and adapted for connection at its opposite endl to a source of uidpressure, a substantially spool-shaped stator member detachably mountedtherein between the ends thereof with its front flange provided withports and terminating short of the front end of said bodyin snug fitting`engagement with the inner Wall thereof andhitsjrear flange being freefrom contact with such inner wall of the body and serving as anattaching ange for bolt-conat the start of the cleaning operationv incontact `with the scale.

While manifestly simple, inexpensive-and durable in construction andpositive and efficient in thoroughly cleaning the entire area of thetubes, this scraper tool promotes economy and maintains maximum boilereiciency, and it'is -so designed that it can be readily assembled anddismembered and its scraper blades can be readily removed and replaced.

necting the stator member to said body, a rotor journaled in said statormember and having an impellermember detachably mounted on that endthereof forwardly of the front stator-flange and in enshrouded relationwith the adjoining end of said body, and scraper elements mounted onthefront face of the impeller member.

J OHN ZILLIOX.

